One of the most rewarding aspects of providing Ceph technical support is helping users simplify workflows for major changes, such as adding or removing multiple hosts in their Ceph clusters.
Ceph scalability is one of its strongest features, allowing operators to add or remove capacity, replace servers, and perform maintenance without downtime.
However, when managing large-scale Ceph clusters, operations like redistributing objects or handling recovery events can become complex and time-consuming. At these scales, additional tools and optimized workflows are essential to ensure smooth operations while maintaining performance and reliability.
Challenges of Ceph Object Redistribution at Scale
Let’s consider an example of growing your Ceph cluster. Whether you’re using ceph orch apply osd or custom tools, after adding new capacity, you might encounter a status like this:
4518 active+remapped+backfill_wait
2.1B (28%) objects misplaced
Here, 28% of the objects need redistribution onto new hosts. While Ceph scalability ensures this process happens transparently, challenges arise when progress looks like this:
Progress: Global Recovery Event [x…………………………..] (6w)
In this extreme scenario, redistribution could take 6 weeks, limiting operators’ ability to throttle, pause, or revert the operation. What if a major event, like a power outage, occurs during this period? While Ceph maintenance ensures data safety, long recovery times add complexity and risk.
Enhanced Control with the Ceph upmap-remapped Tool
To address these challenges, we at CLYSO advocate for enhanced control in Ceph cluster management. A key tool in our arsenal is upmap-remapped, which was originally developed during my time at CERN. This tool allows for more precise control over object redistribution, improving both the reliability and efficiency of large-scale Ceph data migration tasks.
With upmap-remapped, operators can:
- Control the pace of object redistribution
- Minimize performance impact on the cluster
- Safeguard operations during unexpected events
Best Practices for Adding Capacity to Ceph Clusters
This week, we’ve published detailed documentation on adding capacity to Ceph clusters using upmap-remapped. Our step-by-step guide outlines how to:
- Prepare your cluster for new hosts or OSDs.
- Implement controlled object redistribution.
- Monitor progress and ensure efficient recovery.
You can find the full guide here: Improved Procedure for Adding Hosts or OSDs.
Why Choose CLYSO for Ceph Technical Support?
At CLYSO, we specialize in Ceph maintenance, upgrades, and troubleshooting. Whether you’re facing challenges with Ceph object redistribution, need support with Ceph cluster management, or are exploring tools for large-scale Ceph scalability, our experts are here to help.
Don’t hesitate to reach out for personalized assistance and resources to simplify your workflows and optimize your Ceph cluster performance.
